That's a matter for the city's code enforcement office. Every place is slightly different, but I'd ask for code enforcement or permits and licenses. Check city listings online.

Yes, as sushipup1 said, it is a Code enforcement issue. But, bear in mind that because of COVID, many people are having to work from home that normally wouldn't be. What type of noise do they make?

Also, there doesn't have to be a business taking place in the garage for the neighbors to be noisy. A house kitty-corner across the street from us has someone practicing playing the drums in the garage (with the garage door up) several days each week. Would I prefer it not to happen? Yes. Do I let it get to me? No. Nothing I can do about it - it's their right to do that, as long as they don't do it too early in the morning, or too late at night, which they don't. And, the upside is that the drummer is getting better!

It does vary state to state and zone to zone in an area. In my zone, basically you can only run a business if their is no employees , non manufacturing and there is no customers coming to the house. There was one couple who was building furniture and selling the furniture from their house. Complete with a web site. They were shut down.